Pinhole/Cyanotypes

[Toffle]

Hi folks;

Just a quick question while I try some experiments here... Has anyone had experience/success in combining pinhole photography with the cyanotype process? I imagine it must work, though the exposures might be astronomically long. Given that a contact print "new" cyanotype prints out in 2-3 minutes in full sun, how would you calculate exposure times for pinholes? (I have calculated that for the dimensions I am using for my experiments that the optimal pinhole for conventional paper is ~.75mm)

Any tips would be greatly appreciated.

Thanks,

 

[Ray Heath]

g'day Toffle,

not one reply! no-one willing to put it out there?

it's generally advised that cyanotype is far too slow for anything but contact printing

however, why not have a go?

i've actually been thinking about this for a couple of days after a fellow uni student suggested the same thing, she wants to make extremely long exposures, read weeks

i do a lot of exposures on FB paper in home made simple lens cameras. with an ISO of 6 and an aperture of f64, and allowing for RTF, exposures are very often 10's of minutes or more

how to proceed? i guess you'll have to do test shots in multiples of hours to determine ISO.

Ray

 

[Toffle]

Thanks Ray;

I've been doing some crunching. As far as I can tell, if you were making a direct cyanotype print through a .75mm aperture, it would take at minimum 5 hours. How this translates when we start talking about reflected light, I do not know. I'm going to set up my "box" tomorrow morning and check it periodically throughout the day. I could use a larger aperture, but my reading so far indicates that I'm in the right ball park as far as regular pinholes are concerned.

(By the way, yes, I know that even if this works, I'll be creating a negative image.)

Thanks again,

 

[Ray Heath]

an excellent start Toffle,

some questions if i may;

what maths did you use to determine 5hrs?

why .75mm? what maths?

given that f stop equals distance from pinhole to light sensitive material (focal length) divided by diameter of pinhole, what dimensions and maths?

Ray

 

[Vaughn]

You might want to look into the Cyanotype Rex version of the process. It is suppose to deliver camera-speed cyanotypes. It was invented by Terri King. I don't know the details of it, but think it might involve coating the paper with Ferric ammonium citrate...and use it to make your exposure. Then develop the "negative" in the Potassium ferricyanide. Something like that, anyway.

But it sounds like a way to bring down your exposure times.

Vaughn

 

[Toffle]

an excellent start Toffle,

some questions if i may;

what maths did you use to determine 5hrs?

why .75mm? what maths?

given that f stop equals distance from pinhole to light sensitive material (focal length) divided by diameter of pinhole, what dimensions and maths?

Ray

Hi Ray;
I downloaded a pinhole design program from www.pinhole.cz. This gave me my basic figures, which I double-checked... um... somewhere else. (I looked at so many sites, I've forgotten which one) Anyway, my results were similar with both calculations, so I figured I was close.

My figures are as follows:
My coated sheet is 8X10
Focal length is 11"
Which results in an optimal pinhole of .75mm
These numbers, crunched through the pinhole design program, yield an aperture of f373

Compared to measurable exposures at f22, we end up with an exposure between 5 and 10 hours. :confused: (It's a good thing I'm on vacation )

All this being said, numbers are really not my thing. I have struggled with dyslexia all my life (the real thing, not the lazy excuse for not doing homework) and can't always get things in the right order.

I'll try my setup tomorrow and see what happens.

Cheers, mate.

 

[Toffle]

Vaughan,
I haven't heard of that process. It sounds interesting; I'll do some more research. For now, though, I'll stick to Mike Ware's formula. I'm familiar with it. (and I have it.)
Thanks,

 

[Neil Miller]

Tom,

If you get it to work, perhaps you would like to find out about the "pellet process" form of cyanotype - it gives a positive image instead the usual negative image.

Just google "pellet process"

Regards,
Neil.

 

[Toffle]

Tom,

If you get it to work, perhaps you would like to find out about the "pellet process" form of cyanotype - it gives a positive image instead the usual negative image.

Just google "pellet process"

Regards,
Neil.

Thanks Neil;

I'll do that.

I got my test ready to go before bed last night. (about 3:00 AM... don't ask) We woke to about four hours of rain this morning. By the time I moved my setup outdoors, it was about 10:30 AM. It's mostly clear, so I'll let it sit for most of the day and see what I get.

Thanks again,

 

[eddie gunks]

sounds great. i love shooting pinholes. one suggestion. why not use a 6 inch box? you would get an f stop of about 330. that may reduce your exposure times. i shoot 8x10 with this set up and it is a good FL.

keep us posted.

eddie

 

[Toffle]

sounds great. i love shooting pinholes. one suggestion. why not use a 6 inch box? you would get an f stop of about 330. that may reduce your exposure times. i shoot 8x10 with this set up and it is a good FL.

keep us posted.

eddie

Hi Eddie;

My first attempts started with a simple (available) box that could:
1) easily be lightproofed.
2) hold some 8X10 sheets I had already prepped.

That is why my focal length was set at 11" (the depth of my box)

My results... it took about 5 hours to achieve what amounted to slight fogging of the sheet. At 8 hours there was still no appreciable image. My guess is that at this point my paper is more baked than exposed.

We're not finished yet. I will try again with a shallower box, as you suggest, and perhaps a larger aperture. I'm not versed enough on aperture theory or the relative sensitivity of my treated paper to really predict what my exposure times should be. I'm betting if the rain holds off, I may actually have an image soon.

Cheers, (this is fun)

 

[Toffle]

While I'm working towards (waiting for?) success, I am wondering:

Is it actually possible to photograph a scene using cyanotype chemistry at all? The reason for this question is that I don't know how much UV light is reflected in a multi-hued scene. I know that the visible light in front of my camera is being projected on the treated paper inside. That much is plain physics. What I don't know is whether there is enough UV light in that projected image to create an image on the treated paper. (That's physics, too, but nothing that I can quantify.)

Any ideas, before I load up my box camera again?

cheers,

 

[DBP]

As far as I know, relatively few substances reflect UV, so you may be chasing the impossible here. What are you attempting to photograph?

 

[Toffle]

As far as I know, relatively few substances reflect UV, so you may be chasing the impossible here. What are you attempting to photograph?

For now, I have my setup in my backyard. (someplace I can leave it for several hours untouched.) The scene is flowers, trees, sand, and water. I was hoping that over the long (looong) exposure times necessary for cyanotype images there would be enough UV reflected to create a decent image. If I'm mistaken, all I've wasted is a few sheets of treated paper and a few hours sitting in my own backyard.

Cheers,

 

[schorhr]

Hello, first of all, sorry to dig up this rather old topic.

I am interested in a simple photography project as well.
Since Cyanotypes seem to be the simplest project to create pictures via light, I thought to give it a try.
I can see the problem with the exposure time and the low uv-reflection of objects, but maybee the long time, change of the sun and heat is the biggest problem, so I was wondering if one of the "enhanced" cyanotype-formulas would bring other results?

Different methods that are based on cyanotypes to reach very low exposure times can be found on the great site
Dead Link Removed

so this might be a solution? Even if very low UV light is beeing reflected, it might be enough to bring a picture on paper that has been treated with a alternative process?

 

[Loris Medici]

Hi Toffle,

I don't believe you'll be able to get a decent image in those conditions (any cyanotype formula and a ~ f/360 pinhole that is). I remember someone using cyanotype treated paper as negatives (it was an article or gallery in photo.net) and the photographer was using a simple one element lens (very large aperture ~ f/2 - 2.8) to create images outdoors. IIRC, the exposure times were not less than 30 minutes. Then the papers were developed, scanned and inverted in an image editing program giving nice brown positive images...

You may be rowing against a very strong stream (as we say here in Turkey, hope that makes sense to you)...

Regards,
Loris.

For now, I have my setup in my backyard. (someplace I can leave it for several hours untouched.) The scene is flowers, trees, sand, and water. I was hoping that over the long (looong) exposure times necessary for cyanotype images there would be enough UV reflected to create a decent image. If I'm mistaken, all I've wasted is a few sheets of treated paper and a few hours sitting in my own backyard.

Cheers,

 

[schorhr]

I'dd be happy with some skyline/landscape b/w contrast images
Also, I have read up a bit on anthotypes
( http://www.alternativephotography.com/articles/art098.html )
since it will be easier and more fromscratch if I do this with kids.
Some plants only need 1-3 hours of exposure, which is relativly low, I wonder what light spectrum does the trick- so maybee its more likely to use this in a pinhole camera thats steadily fixed to a high contrast landscape or skyline for example?

Since it is positive developing too, it would be ready to view instantly, only downside is that there seems to be no way to stop the exposure except for keeping it stored in a dark place...

 

[schorhr]

Sorry for doubleposting, but has anyone tried cyanotype rex?
This seems to be the answer to direct photography, since the improved versions will make it possible to use "regular" light spectrum & very quick exposure:
http://www.f295.org/Pinholeforum/forum/Blah.pl?b-apd/m-1137519426/

 

[Loris Medici]

Hi,

I would like to point you all who are intended to make in-camera exposure using *any* cyanotype formula to the address I provide below :

Dead Link Removed

In short: Don't waste your time...

Regards,
Loris.

Sorry for doubleposting, but has anyone tried cyanotype rex?
This seems to be the answer to direct photography, since the improved versions will make it possible to use "regular" light spectrum & very quick exposure:
http://www.f295.org/Pinholeforum/forum/Blah.pl?b-apd/m-1137519426/

 

[Akki14]

I'dd be happy with some skyline/landscape b/w contrast images
Also, I have read up a bit on anthotypes
( http://www.alternativephotography.com/articles/art098.html )
since it will be easier and more fromscratch if I do this with kids.
Some plants only need 1-3 hours of exposure, which is relativly low, I wonder what light spectrum does the trick- so maybee its more likely to use this in a pinhole camera thats steadily fixed to a high contrast landscape or skyline for example?

Since it is positive developing too, it would be ready to view instantly, only downside is that there seems to be no way to stop the exposure except for keeping it stored in a dark place...

I do wonder which plants take that short of a time because all of my anthotype (okay, 2-3 of them I've tried) exposures last about 3 days. The best so far has been purple iris juices (crush with mortar&pestle, filter&squeeze juice through a coffee filter and paint on watercolour paper). I've tried purple sage (no solar colour change after 3-4 days) and red cabbage (raw, finely chopped in food processor, squeezed and filtered as above). now having read the article, I'll try the nasturium leaves thing if I get any more sunshine after today).

It's not really positive developing, as in you can't just shoot in a camera. You put a negative over the dried paper that you've covered with the juices then expose to sunlight until an image is produced (pick up some small splitback frames on ebay for cheap if you just want to try this out).

 

[schorhr]

I would like to point you all who are intended to make in-camera exposure using *any* cyanotype formula to the address I provide below :
Dead Link Removed
In short: Don't waste your time...

I am a bit confused, probably its because my lack of english skills, but did i misread that its possible to make faint images?
I am not talking about sharp, high contrast images, just a basic method for a litle experimenting.

@Akki14
I have bought a "face sun" at a fleamarket (3 Euro=$4), they are available at ebay and other sources for about 5-20 dollars.
( http://images.google.com/images?q=gesichtsbräuner )
It has 4 UV lamps and therefore probably works much faster then the sun, unfortunaly I have just tried wine and red beat juice with small samples in the sun (I left it out there for 3 weeks due to bad weather all the time).

 

[Akki14]

Wow that's really cheap for a facial tanning unit. I paid something like 20GBP for mine, I think. I haven't tried anthotypes under the facial tanning unit... I've only recently figured out that I could prop up the unit so it's face down (resting on 4 120 spools) so my cyanotype contact print exposure times are down to about 4-5 minutes (!)

I'll have to go back to experimenting with the anthotypes sometime, but I've signed myself up to quite a few print exchanges on here so I'm thinking more about them at the moment.

 

[schorhr]

Well, using wine/juice its pretty easily preperated, I just let regular paper soak overnight, but I'll get some "sokier" paper for the anthotypes ;-)

Yes it was really a good deal, and they seem to get more expensive at ebay too, but the german auction site hood has them still cheap (under 10 Euros).
The fleamarket was pure luck. It was a smaller indoor fleamarket and I got it at the last stand ;-)
I tried the anthotype with IR-Light and regular light, but that had no effect. I was hoping the UV light will reduce the process to a few hours, but I am sceptical. Since the device is good use for cyanotype and almost any other process (also for electronic boards) there is no money lost.
I might build some casing as others did, but I guess I could just stand stuff infront of it.
Any idea how long these units can run before overheating? (at least the IR-Bulb we have is only suitable for up to 20 minutes)

 

[Akki14]

Mine is turned on and off by a built in timer. It's set at a maximum of 60minutes... Please note that these are NOT meant to be stared at and I generally leave the room completely when I'm running mine. They're suppose to come with little goggles to protect your eyes if you're using them to get a tan on your face.
I found my times just standing a frame up in front of it, about 1 foot (30cm) away from it took 30+minutes for cyanotype compared to the 120 spool height times of 4-5minutes. I'd definitely suggest building something, even if it is just resting it on a neat pile of books on either end to hold it up.

 

[schorhr]

Thanks for the info.
Mine has a 30 minute timer and I was wondering if devices like this can run longer if its not intended for tanning.
Yes, I have googles and intend to not be close to it